Then:
During it's first year of service, 46,994 pieces of mail were handled by the Marine Post Office. During the second year of operation, the volume of mail increased by almost 400 percent with a total of 175,850 letters delivered to more than 19,000 ships that passed Detroit that season.

In its hay day, traffic on the Detroit river was so heavy that it was necessary for the steam tug to tow a small fleet of rowboats. These rowboats made it possible to meet the demand and service several passing ships simultaneously.